Lubricating devices for sewing machines



19% 5. J. KETTERER ETAL 3929495549 LUBRICATING DEVICES FOR SEWING MACHINES Filed Feb. 8, 1965 INVENTORS. Siunley J. Kefierer and Michael F. lvomku BY A if ,Kjbww 7 XMTQBNEY United States Patent 3,294,649 LUBRIATING DEVICES FOR SEWING MACHINES Stanley J. Ketterer, Morris Plains, and Michael F. Ivanko, Roclraway, NJ assignors to The Singer Company,

New York, N.Y., a corporation of New Jersey Filed Feb. 8, 1965, Ser. No. 430,904 Claims. (Cl. 112-156) This invention relates to lubricating devices for sewing machines and more particularly to a device for lubricating a raceway of a loop-taker.

In sewing machines having a loop-taker in which a rotary member carrying a loop-seizing beak rotates around a stationary member, lubricating the bearing surface between the rotary member and the stationary member has been a perennial problem. The problem is particularly frustrating because if too much lubricant is supplied to the bearing surface between the rotary member and the stationary member, the lubricant will spatter onto work material which is supported only a fraction of an inch away on the work-supporting bed. In addition, the lubricant will soil thread as the thread is manipulated by the loop-taker to form stitches, and may even run onto a thread supply housed in the stationary member. (3n the other hand, if the bearing surface between the rotary member and the stationary member is insufficiently lubricated, the members will overheat and wear out in a short period of time.

It is therefore, an object of this invention to provide a device for consistently supplying just the right amount of oil to a raceway of loop-taker.

Another object of the invention is to provide a device in accordance with the foregoing object which is uncomplicated in structure and can be easily added to existing sewing machines.

When the invention is embodied in a loop-taker of the type disclosed in a United States patent of Ketterer et al., No. 3,063,392, granted November 13, 1962, in which a bobbin driver is pressed against a bobbin in order to replenish thread on the bobbin, a wick is clamped by a spring clip to the hub portion of the rotary member of the loop-taker so that one extremity of the wick contacts oil which collects on an end of a lubricated bearing which supports the loop-taker shaft. The bobbin driver has a peripheral extension through which two holes are formed. The other extremity of the wick is looped through the two holes in the bobbin driver so that the loop thus formed contacts the bearing surface between the rotary member and the stationary member only when the bobbin driver is pressed against the bobbin as for replenishing thread on the bobbin.

Other objects and a .fuller understanding of the invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings in which:

FIG. 1 is a front elevational view, partly in section, of a loop-taker with a bobbin driver and a lubricating wick retracted as for sewing;

FIG. 2 is a front elevational view, partly in section, of the loop-taker of FIG. 1 with the bobbin driver pressed against the bobbin as for replenishing thread on the bobbin and the lubricating wick pressed against the bearing rib on the bobbin case; and

FIG. 3 is a perspective view of the bobbin driver and the lubricating wick.

With reference to the drawings, the invention is illustrated as embodied in a sewing machine of the type disclosed in the aforementioned United States patent of Ketterer et al., No. 3,063,392, to which attention is directed for a complete disclosure of the loop-taker and the bobbin thread replenishing mechanism.

In general, the sewing machine has a frame of which only a portion of a work-supporting bed 10 is shown. Mounted in the bed is a bearing id for a loop-taker shaft 12. The hearing has a bore 13 for a wick 14 which holds a supply of oil to lubricate the bearing.

Fixed on an extremity of the loop-taker shaft 12 is a loop-taker, indicated generally at 15. The loop-taker has a cup-shaped rotary member 16 which rotates around a stationary member constituting a bobbin case 17. The rotary member has a hub portion .18, and a flange portion 19 carrying a loop-seizing beak 20. The loop-taker is aflixed to the loop-taker shaft by a setscrew 21 in the hub portion 18.

The bobbin case 17 is held stationary by means of a lug 22 connected to the frame and extending into a notch 23 in the bobbin case. An annular groove 24 in the flange portion 19 of the rotary member 16 provides a raceway 25 for a bearing rib 26 on the bobbin case. A gib 27 which is removably connected to the rotary member closes the end of the raceway.

Journaled inside the bobbin case 17 on a stud 28 and held on the stud by a screw 29 is a bobbin 30. The bobbin is opposed by a shiftable bobbin driver 31 housed in the rotary member 16. The bobbin driver is fixed on an extremity of a push rod 32 which is slidably held in the hollow loop-taker shaft 12 and rotates with the loop-taker shaft.

A peripheral extension on the bobbin driver 31 constitutes a clamping member 33 for clamping a loop of thread (not shown) which has been seized by the loopseizing beak 24 against the back 34 of the beak between a spring 35 and the back of the beak when the bobbin driver is pressed against the bobbin 30 as for a bobbin thread replenishing operation. A :gap 36 in the flange portion 19 of the rotary member 16 provides a guide for the shifting movement of the clamping member 33. In order to provide just the right amount of lubrication for the bearing rib 26 on the bobbin case 17, a wick is clamped to the hub portion 18 of the rotary member 16 by a spring clip 38 so that one extremity 39 of the wick contacts an end 40 of the bearing 11 to pick up oil which has collected on the end of the bearing from the supply of oil in the bore 13 in the hearing. The wick is held in an arched portion 41 of the spring clip.

Two holes 42 are formed in the clamping member 33 which extends from the periphery of the bobbin driver 31, and the other extremity 43 of the wick 37 is looped through the two holes 42 so that the loop of the wick contacts the biasing rib 26 on the bobbin case 17 only when the bobbin driver is pressed against the bobbin as for replenishing thread on the bobbin.

In operation, the invention can be easily added to existing sewing machines by simply forming the two holes 42 in the clamping member 33 of the bobbin driver 31 and clamping the wick 37 to the hub portion 18 of the rotary member 16 by means of the spring clip 38. The wick draws from oil which has collected on the end 4% of the bearing 11 from the supply of oil in the bore 13 in the bearing. In practice, it has been found that just the right amount of oil is applied to the bearing rib 26 on the bobbin case 17 as the bobbin driver 31 is intermittently pressed against the bobbin 30 during bobbin thread replenishing operations. And, in applying oil to the bearing rib 26 only during bobbin thread replenishing operations, there is less change of spattering oil onto work material than there would be if oil were applied to the bearing rib during sewing operations.

Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention.

Having thus set forth the nature of the invention, what is claimed herein is:

1. A lubricating device for a sewing machine having a frame, a shaft mounted in the frame, and a loop-taker mounted on the shaft, said loop-taker having a rotary member, a stationary member and bearing surfaces between the rotary and stationary members, said lubricating device comprising a wick supported on said rotary mem ber, means for intermittently shifting a portion of the wick against one of the bearing surfaces between the rotary and stationary members of the loop-taker, and means for applying oil to the wick.

2. A lubricating device for a sewing machine having a frame, a shaft mounted in the frame, and a loop-taker mounted on the shaft, said loop-taker having a rotary member, a stationary member, bearing surfaces between the rotary and stationary members, a bobbin mounted in the stationary member, and a bobbin driver shiftably housed in the rotary member for replenishing thread on the bobbin when pressed against the bobbin to rotate the bobbin, said lubricating device comprising a wick supported on said rotary member, wick-engaging means on said bobbin driver for shifting a portion of said wick into contact with one of the bearing surfaces between the rotary and stationary members of the loop-taker when the bobbin driver is pressed against the bobbin as for replenishing thread on the bobbin, and means for applying oil to the wick.

3. A lubricating device for a sewing machine having a frame, a bearing mounted in the frame, a shaft journaled in the bearing, a supply of oil for the bearing, and a loop-taker mounted on the shaft, said loop-taker having a rotary member, a stationary member, a bearing surface between the rotary and stationary members, a bobbin mounted in the stationary member, and a bobbin driver shiftably housed in the rotary member for replenishing thread on the bobbin when pressed against the bobbin to rotate the bobbin, said lubricating device comprising a wick, means for connecting the wick to the rotary member so that one extremity of the wick contacts oil which collects on an end of said bearing, and means for connecting the wick to the bobbin driver so that the other extremity of the wick contacts the bearing surface between the rotary and stationary members of the looptaker only when the bobbin driver is pressed against the bobbin as for replenishing thread on the bobbin.

4. A lubricating device for a sewing machine having a frame, a bearing mounted in the frame, a shaft journaled in the bearing, a supply of oil for the bearing, and a loop-taker mounted on the shaft, said loop-taker having a rotary member, a stationary member, a bearing surface between the rotary and stationary members, a bobbin mounted in the stationary member, and a bobbin driver shiftably housed in the rotary member for replenishing thread on the bobbin when pressed against the bobbin to rotate the bobbin, said lubricating device comprising a wick, means for connecting the wick to the rotary member so that one extremity of the wick contacts oil which collects on an end of said bearing, and a peripheral extension on the bobbin driver having two holes therethrough in which the other extremity of the wick is looped with the loop of the wick facing the bearing surface between the rotary and stationary members of the loop-taker so that said loop contacts said bearing surface only when the bobbin driver is pressed against the bobbin as for replenishing thread on the bobbin.

5. A lubricating device for a sewing machine having a frame, a bearing mounted in the frame, a shaft journaled in the bearing, a supply of oil for the bearing, and a loop-taker mounted on the shaft, said loop-taker including a rotary member having a hub portion and an annular raceway, a stationary member having a bearing rib journaled in said raceway, a bobbin mounted in the stationary member, and a bobbin driver shiftably housed in the rotary member for replenishing thread on the bobbin when pressed against the bobbin to rotate the bobbin, said lubricating device comprising a wick, a spring clip connecting the wick to the hub portion of the rotary member so that one extremity of the wick contacts oil which collects on an end of said bearing, and a peripheral extension on the bobbin driver having two holes therethrough in which the other extremity of the wick is looped with the loop of the wick facing the bearing rib on the stationary member of the loop-taker so that said loop contacts said bearing rib only when the bobbin driver is pressed against the bobbin as for replenishing thread on the bobbin.

References Cited by the Examiner UNITED STATES PATENTS 11/1960 Reeber et al. 112256 9/1964 Schenkengel ll256 

1. A LUBRICATING DEVICE FOR A SEWING MACHINE HAVING A FRAME, A SHAFT MOUNTED IN THE FRAME, AND A LOOP-TAKER MOUNTED ON THE SHAFT, SAID LOOP-TAKER HAVING A ROTARY MEMBER A STATIONARY MEMBER AND BEARING SURFACES BETWEEN THE ROTARY AND STATIONARY MEMBERS, SAID LUBRICATING DEVICE COMPRISING A WICK SUPPORTED ON SAID ROTARY MEM- 